I have a 91 350 sdl that I bought from a guy about 2 years ago. I have never driven the car I think it has the head gasket oil passage problem. I have started the car once to move it 4 ft. and after shut down I get oil spewing out the tail pipe. Has Mercedes perfected the head gasket to replace it or could it be stretched head bolts. I have never seen a real good explanation of why this happens. The car has 190,000 miles on it and is in very good condition other than this problem. anyone have any info?

Thanks

Enough info to keep you busy reading until May Day.

ASSUMING:
head gasket problems without compression/leak down testing does WHAT?
(Answer: Mis-Informs)

'Could be a HG,Or could be "Wallered Out" Cylinder(S). Etc.,Etc.,Etc.

KNOW what's wrong with this 3.5 before trying to Kiss Pandora!

Smartest Plan would be to have a 3 Liter OM603 Lower End of Good Provenance
Waiting in the Wings,In Case Bad goes Worse.
(It Plugs Right In to the Old Head of the 3.5 liter)

__________________
'84 300SD sold
124.128

If there's oil coming out of the tailpipe it probably has a blown turbo...

-J

__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

I'm gonna say ditto on the turbo being a problem. If it was oil consumption into the engine the thing would have run away on you but you were able to shut it off normally so I see no reason to assume the worst yet. It's more likely the oil is going to the turbo and out the tail pipe.

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Steve A
92 W140 OM603
97 VW Jetta TDI
90 Passat variant TDI 6 speed MT
94 Chevy K1500 6.5TD
05 E320 CDI
+ others

Pull the number one injector or glow plug. Disable the injector by using the hard line nut if removing the glow plug. Crank the engine. If oil is blown out of the cylinder it is the oil passage.

If the glow plug looks dry it probably is the turbo as mentioned. Another test is to remove the boot between the tubo and the engine intake. It may be a metal crossover pipe on your model. Lots of oil present of course it is the turbo.

Good advice, but know that if the cross over pipe is full of black tarry goo that is a normal byproduct of a properly functioning evil EGR valve. Don't confuse that with oil from a blown turbo.

Wear gloves, that black snot is the worst to get off your fingers. Even with GoJo, it barely makes a dent in it.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

When my turbo went south the 2nd time I could take that pipe off and literally pour oil out of it.

-J

To clarify,

the EGR goo is more like a clogged drain pipe or arteries.

turbo blowout, the oil is liquid and it pours out.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

Yup. The EGR goop is about the consistency of peanut butter.

-J

Peanut butter that has sat out for a month.....!

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Thanks for the imput I will try the test mentioned.